Preparation method for carbon material anti-oxidation coating

Abstract

The invention belongs to a carbon material anti-oxidation coating technique, and relates to a preparation method for a carbon material anti-oxidation coating. The coating mainly comprises 30 to 50 percent of SiC, 1 to 10 percent of Al(OH)3, 15 to 35 percent of SiO2 and 5 to 40 percent of kaolin, and is prepared by the following steps: dissolving Al(OH)3 in H3PO4 in a proportion of 5 to 15 ml / g; adding water into the mixture to dilute the mixture and then mixing the diluted mixture with the other components by stirring; brushing the obtained coating material on a surface of the carbon material; curing the coating in a baking box at a low temperature for use. When a mark needs to be displayed on the surface of the carbon material, 10 to 40 percent of TiO2 powder is added into the coating. By using the method, the anti-oxidation coating of compact structure and high anti-oxidation performance can be formed through only one brushing process and one curing process in the baking box at a low temperature; and the anti-oxidation coating is oxidized for 15 hours in static air of 700 DEG C with weight-loss ratio no more than 1 percent; therefore, the method is particularly suitable for rapid anti-oxidation processing in the actual production of the carbon material.

Description

technical field [0001] The invention belongs to the carbon material anti-oxidation coating technology, and relates to a preparation method of the carbon material anti-oxidation coating. Background technique [0002] Carbon materials, including carbon, graphite and carbon / carbon composite materials, are a new type of material that is currently being researched and developed in the world's new technology fields. It has attracted great attention in the fields of aviation, aerospace, nuclear energy and many civil industries, especially Above 2000°C, they can still maintain their excellent mechanical properties, so they are also ideal ultra-high temperature structural materials. However, carbon begins to oxidize in an aerobic atmosphere at 370°C, and oxidizes rapidly when it is higher than 500°C. If it is polluted or in salt spray air, carbon / carbon composites begin to oxidize at around 450°C, and the oxidation weight loss makes its mechanical properties decline. , when the oxid...

AI Technical Summary

Problems solved by technology

Although these two patents have a good anti-oxidation effect, due to the use of resin or organic substances such as resin in the organic coating, there is a lot of pollution to the construction environment, which does not meet environmental protection requirements.

And the Chinese patent ZL200610145667.6, the title of the invention "An Anti-oxidation Coating of Carbon / Carbon Composite Material", discloses a composite coating whose main component is Al(OH) 3 , Zn 3 (PO 4 ) 2 4H 2 O, Na 2 B 4 o 7 10H 2 O, SiO 2 , B, etc., the carbon / carbon composite anti-oxidation coating obtained after two treatments has good anti-oxidation effect and good environmental protection, but the only disadvantage of the coating is poor water solubility, and the coating will unstable

[0006] Due to the characteristics of the production process of carbon materials, especially carbon / carbon composite brake discs, after oxidation protection, post-process processing is required, such as the installation of key clips, etc. Due to the fact that there are very few missing coatings in the actual operation process, Or in the subsequent installation or handling process, due to bumping, some parts of the coating are damaged. At this time, a simple and fast anti-oxidation coating technology is needed to recoat the coating, and the content disclosed in the above-mentioned publications cannot be simple and fast. Repairing the anti-oxidation coating